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in subjects: "37 Inorganic, Organic, Physical And Analytical Chemistry"  
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Plutonium isotopic analysis of highly enriched mixed oxides

Description: We investigated the analysis method used by the International Atomic Energy Agency (IAEA) to determine the plutonium isotopic composition of highly enriched mixed oxides (MOX). The IAEA currently uses the Cicero multichannel analyzer and the IAEAPU algorithm for its analysis. In our investigation the plutonium isotopic measurements were found to be good for PuO/sub 2/ powder or low-enriched MOX, but acceptable for highly enriched MOX in IAEA special nuclear material (SNM) accountability applica… more
Date: August 1, 1986
Creator: Clement, S. D. & Augustson, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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RIMS diagnostics for laser desorption/laser ablation

Description: Laser desorption mass spectrometry is a useful method for interrogating materials and events at or near surfaces. Laser desorption/ablation combined with Resonance Ionization Mass Spectrometry (RIMS) provides a powerful tool to obtain information on chemical composition and speciation and, in some cases, internal and translational energy distributions. The application of this technique to the interrogation of materials and interfaces is discussed for several systems, including the analysis of c… more
Date: January 1, 1986
Creator: Apel, E. C.; Nogar, N. S.; Miller, C. M. & Estler, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low cost hydrogen/novel membrane technology for hydrogen separation from synthesis gas, Phase 1. [Poly(methyl pentene) and poly(etherimide)]

Description: This report summarizes the development of polymer membranes useful in the separation of hydrogen from coal-derived synthesis gas during period 1 October 1985--30 September 1986. During the last year several high performance membranes were developed for the separation of hydrogen from nitrogen and carbon monoxide. The heat resistant resins poly(methyl pentene) (TPX), Mitsui Petrochemical Industries, New York, NY and poly(etherimide) (ULTEM, General Electric, Pittsfield, MA) have been selected as… more
Date: January 1, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Trends in resonance ionization spectroscopy

Description: The author reviews the history of resonance ionization spectroscopy and then comments on the delineations of RIS with reference to many related laser processes. The substance of the paper deals with the trends in RIS and especially how the needs for sensitive analytical methods have overshadowed the orginal plan to study excited species. 9 refs., 1 fig.
Date: January 1, 1986
Creator: Hurst, G.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Resonance ionization mass spectrometry at Los Alamos National Laboratory

Description: Two approaches to RIMS will be discussed here. The first is the use of continuous-wave (cw) dye lasers as the ionization source. Continuous excitation effectively matches the ionization to the evaporation of sample from a resistively heated filament, providing for efficient use of the sample. In addition, cw ionization permits pulse counting detection, necessary for the measurement of large isotope ratios on small samples. In the cases of lutetium and technetium discussed below, average ionizat… more
Date: January 1, 1986
Creator: Miller, C. M.; Nogar, N. S.; Apel, E. C. & Downey, S. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Atlas of atomic spectral lines of plutonium emitted by an inductively coupled plasma

Description: Optical emission spectra from high-purity Pu-242 were generated with a glovebox-enclosed inductively coupled plasma (ICP) source. Spectra covering the 2280 to 7008 Angstrom wavelength range are presented along with general commentary on ICP-Pu spectroscopy.
Date: September 1, 1986
Creator: Edelson, M. C.; DeKalb, E. L.; Winge, R. K. & Fassel, V. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparisons of the structure, stability and electron distribution of nitrobenzenes and nitro-sym-triazines

Description: Nitrobenzenes are a well known class of stable organic compounds. Nitro-sym-triazines are not known, although other substituted triazines are very well known. To investigate what properties the nitrotriazines might have, should they be synthesized, we performed molecular orbital calculations for nitrotriazine (NTZ), dinitrotriazine (DNTZ), and trinitrotriazine (TNTZ). Nitrobenzenes with analogous nitrogroup substitution were also studied to provide a check on the calculations. In particular, ni… more
Date: January 1, 1986
Creator: Ritchie, J.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear data for Gd-153 production

Description: A compilation of neutron activation cross section data is provided. Data on this gadolinuim is needed because of its use as the working ingredient in an advanced medical scanning machine that can detect loss of bone minerals such as calcium, a possible cause of the disease osteoporosis. 4 refs.
Date: January 1, 1986
Creator: Holden, Norman E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nondestructive measurements in support of Waste Isolation Pilot Plant at Rockwell Hanford Operations: problems and methods

Description: The 234-5Z Analytical Laboratory, located in the 200 West Area of the Hanford Site, has been requested to provide waste package measurement capability for both the Plutonium/Uranium Extraction (PUREX) Plant and Plutonium Finishing Plant (PFP) in support of the Waste Isolation Pilot Plant (WIPP) Waste Acceptance Criteria (WAC). The requested WIPP values are sensitive to changes in isotopic distribution. Unfortunately, the determination of the isotopic distribution of an individual waste item or … more
Date: May 1, 1986
Creator: Westsik, G.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improved laboratory assays of Pu and U for SRP purification and finishing processes

Description: Significant improvements have been made in routine assay techniques for uranium and plutonium as part of an effort to improve accountability at the Savannah River Plant (SRP). Emphasis was placed on input/output accountability points and key physical inventory tanks associated with purification and finishing processes. Improvements were made in existing assay methods; new methods were implemented; and the application of these methods was greatly expanded. Prior to assays, samples were validated… more
Date: January 1, 1986
Creator: Holland, M K & Dorsett, R S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Automatic titrator for high precision plutonium assay

Description: Highly precise assay of plutonium metal is required for accountability measurements. We have developed an automatic titrator for this determination which eliminates analyst bias and requires much less analyst time. The analyst is only required to enter sample data and start the titration. The automated instrument titrates the sample, locates the end point, and outputs the results as a paper tape printout. Precision of the titration is less than 0.03% relative standard deviation for a single det… more
Date: January 1, 1986
Creator: Jackson, D. D. & Hollen, R. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Application of Synchrotron Radiation to X-Ray Fluorescence Analysis of Trace Elements

Description: The development of synchrotron radiation x-ray sources has provided the means to greatly extend the capabilities of x-ray fluorescence analysis for determinations of trace element concentrations. A brief description of synchrotron radiation properties provides a background for a discussion of the improved detection limits compared to existing x-ray fluorescence techniques. Calculated detection limits for x-ray microprobes with micrometer spatial resolutions are described and compared with exper… more
Date: August 1, 1986
Creator: Gordon, B. M.; Jones, K. W. & Hanson, A. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Description of an XRF system for multielemental analysis

Description: An X-ray fluorescence (XRF) system which uses radioisotopes in an orthogonal configuration between the source, sample, and detector is described. The advantage of such a system is that for large (bulk) samples or for in vivo measurements the background due to Compton scattering in the sample is minimized. High reproducibility for nonuniform samples is obtained by reducing the sample size and thus the effects of non-uniformity in the spatial response of such a system. Germane to any accurate ana… more
Date: January 1, 1986
Creator: Wielopolski, L.; Zhang, R. & Cohn, S.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synchrotron radiation as a source for quantitative XPS: advantages and consequences

Description: Synchrotron radiation (SR) has a variety of properties which make it an attractive source for quantitative x-ray photoelectron spectroscopy (XPS). Among the most significant are high intensity and tunability. In addition, the intensity of the dispersed radiation is comparable to laboratory line sources. Synchrotron radiation is also a clean source, i.e., it will not contaminate the sample, because it operates under ultra-high vacuum conditions. We have used these properties to demonstrate the a… more
Date: January 1, 1986
Creator: Rosseel, T. M.; Carlson, T. A.; Negri, R. E.; Beall, C. E. & Taylor, J. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Application of atomic vapor laser isotope separation to the enrichment of mercury

Description: Workers at GTE/Sylvania have shown that the efficiency of fluorescent lighting may be markedly improved using mercury that has been enriched in the /sup 196/Hg isotope. A 5% improvement in the efficiency of fluorescent lighting in the United States could provide a savings of approx. 1 billion dollars in the corresponding reduction of electrical power consumption. We will discuss the results of recent work done at our laboratory to develop a process for enriching mercury. The discussion will cen… more
Date: September 1, 1986
Creator: Crane, J. K.; Erbert, G. V.; Paisner, J. A.; Chen, H. L.; Chiba, Z.; Beeler, R.G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Resin bead methodology as applied to fuel burn-up and fissile inventories

Description: A new technique has been developed that allows acquisition of samples from matrices difficult to access. While the examples given in this paper are from the nuclear field, the technique is readily modified to address other areas. The technique involves obtaining samples on resin beads; each bead then comprises a sample for mass spectrometric analysis. Through the application of isotope dilution, concentrations of the target elements can be obtained in addition to their isotopic compositions. Ex… more
Date: January 1, 1986
Creator: Smith, D. H.; Walker, R. L. & Carter, J. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Unusual bond paths in organolithium compounds

Description: We have applied the topological method to a number of organolithium compounds. The wavefunctions were determined with GAUSSIAN-82 using 3-21G basis set and fully optimized geometries. Gradient paths were obtained using the RHODER package and critical points were located using EXTREME. These results indicate the unusual nature of organolithium compounds. The strange bond paths arise mainly from the ionic nature of the C-Li interaction. We suggest that the term ''bond path'' may best be suited fo… more
Date: January 1, 1986
Creator: Bachrach, S.M. & Ritchie, J.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Determination of the Occurrence of Gold in an Unoxidized Carlin-Type Ore Sample Using Synchrotron Radiation

Description: The occurrence of the so-called invisible gold in two unoxidized Carlin-type gold samples from Nevada have been determined using synchrotron x-ray fluorescence (SXRF) analysis at the National Sychrotron Light Source, Brookhaven National Laboratory. The samples were a bedded sample from the east ore zone of the Carlin deposit and a breccia sample from Horse Canyon. Preliminary results show that gold is found only in the Horse Canyon breccia sample. Experimental details including other x-ray line… more
Date: January 1, 1986
Creator: Chen, J. R.; Chao, E. C. T.; Minkin, J. A.; Back, J. M.; Bagby, W. C.; Rivers, M. L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low cost hydrogen/novel membrane technology for hydrogen separation from synthesis gas, Phase 1. [Poly(etherimide) and poly(ether-ester-amide) membranes]

Description: During the last quarter several high performance membranes for the separation of hydrogen from nitrogen, carbon monoxide, hydrogen sulfide and carbon dioxide. The heat-resistant resin poly(etherimide) has been selected as the polymer with the most outstanding properties for the separation of hydrogen from nitrogen and carbon monoxide. Flat sheet and hollow fiber poly(etherimide) membranes have been prepared and evaluated with pure gases and gas mixtures at elevated pressures and temperatures. M… more
Date: January 1, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low cost hydrogen/novel membrane technology for hydrogen separation from synthesis gas

Description: To make the coal-to-hydrogen route economically attractive, improvements are being sought in each step of the process: coal gasification, water-carbon monoxide shift reaction, and hydrogen separation. This report addresses the use of membranes in the hydrogen separation step. The separation of hydrogen from synthesis gas is a major cost element in the manufacture of hydrogen from coal. Separation by membranes is an attractive, new, and still largely unexplored approach to the problem. Membrane … more
Date: February 1, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Availability of enriched stable isotopes: present status and future prospects

Description: The Electromagnetic Isotope Enrichment Facility (EMIEF) is currently used to produce 225 enriched stable isotopes of 50 elements. Among these are included most of the known elements with stable isotopes except for the noble gases, certain light elements, monisotopic elements, etc. The EMIEF can also be used to produce enriched samples of radioactive species, most notably the isotopes of uranium and plutonium. These enriched materials are placed in either the Sales Inventory of in the Research M… more
Date: September 18, 1986
Creator: Hoff, R.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure of tris(trimethylsilylcyclopentadienyl)uranium(III), ((CH/sub 3/)/sub 3/SiC/sub 5/H/sub 43/U. [Tris(trimethylsilylcyclopentadienyl)uranium]

Description: Crystals of ((CH/sub 3/)/sub 3/SiC/sub 5/H/sub 4/)/sub 3/U are orthorhombic, Pbca, with a = 22.630(8), b = 29.177(10) and c = 8.428(3) A at 23/sup 0/C. For Z = 8 the calculated density is 1.551 g/cm/sup 3/. The structure was refined by full-matrix least-squares to a conventional R factor of 0.041 (2251 data, F/sup 2/ > 2 sigma(F/sup 2/)). The uranium atom is bonded to the three cyclopentadienyl rings in a pentahapto fashion and is in the plane of the ring centroids. The U to ring distances are … more
Date: February 1, 1986
Creator: Brennan, J.; Andersen, R. A. & Zalkin, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In vivo monitoring of toxic metals: assessment of neutron activation and x-ray fluorescence techniques

Description: To date, cadmium, lead, aluminum, and mercury have been measured in vivo in humans. The possibilities of monitoring other toxic metals have also been demonstrated, but no human studies have been performed. Neutron activation analysis appears to be most suitable for Cd and Al measurements, while x-ray fluorescence is ideally suited for measurement of lead in superficial bone. Filtered neutron beams and polarized x-ray sources are being developed which will improve in vivo detection limits. Even … more
Date: January 1, 1986
Creator: Ellis, K.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of a standard bench-scale cell for electrochemical studies on inert anodes. Inert Anode/Cathode Program

Description: Objective of this work was to develop a standard bench-scale cell for performing short-term ac and dc polarization studies on inert anode candidate materials in molten cryolite. Two designs for electrochemical cells were developed and successfully evaluated in short-term experiments. Both cells consisted on the inert anode as a small cylindrical specimen partially sheathed in alumina, an Al/Al/sub 2/O/sub 3/ reference electrode, and a cryolite bath saturated in alumina. The difference between t… more
Date: July 1, 1986
Creator: Windisch, C. F. Jr. & Boget, D. I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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